Preheater for oil burners



Dec. 19, 1933. N. R. THIBERT FREE-[EATER FOR OIL BURNERS Filed Sept. 1, 1951 MIN MN W x? m Patented Dec. 19, 1933 NT OF ER PREHEATER FOR OIL BURNERS Napoleon R. Thibert, Worcester, Mass. Application September 1, 1931. Serial No. 560,600

3 Claims. (or; s s7) Thisinvention relates to a liquid fuel burner. The principal objects of the invention are to provide a preheater reduced to its simplest form; to provide a liquid fuel reservoir so combined with the burner and so located that heat from the burner willbe conveyed to the surface of the fuel so as to vaporize the fuel in the reservoir before it gets into the grooves of the burner in which it ignites, and to provide a con- ,;struction for eliminating the formation of car-- bon.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawing, in which Fig. 1 is a side view of a burner constructed in accordance with this invention;

Fig. 2 is a plan of the burner with the cylindrical sheet metal walls removed, and

Fig. 3 is a diametrical sectional view on. the

line 3--3 of Fig. 2.

This invention is shown as applied to a burner which in itself is the subject of prior Patents 1,888,019 and 1,890,593.

Thisburner is made of a casting 10 having a central supporting stem 9 to enter a notch in a supporting frame 8. A nut '7 is used to secure it in fixed position. At the top it is shown as provided with two annular grooves 11 and 12 concentric with each other. On the outside of the walls of the two grooves are circular shoulders 13 for supporting concentric perforated sheet metal tubes 14, as is well understood. The shape, however, need not be circular.

. materially above the burner grooves 11 and 12 and is provided with a loose cap 19 on the top. This cap is loose to provide a vent. As explained in my previous patents, one purpose of this tube and cap is to reflect radiant heat downwardly ;and in this case-this heat is reflected to the bottom of the well.

The liquid fuel enters through a pipe 20 into an oil storing and preheating chamber 21 which is shown as of a general circular shape and hollow throughout and communicates with the well 15 at the center. This chamber 21 is shallow and presents a wide upper surface to receive the heat from above. The oil is admitted freely to this preheating chamber. The oil rises into a series of radial horizontal conduits 22 located in radial arms 23 which constitute apart of the casting as does the preheating chamber 21. These radial passages open into the bottoms of the two grooves 11 and 12 at fourpoints around the circumference, in the form shown.

When the burner is to be lighted the oil turned on and it flows into the grooves 22 and then, being lighted, heat is generated. Part of the radiant heat is reflected downwardly in the central tube 17 with the cap at the top. An intense heat is generated here and is conducted through the oil down into the well and into the top of the liquid fuel in the reservoir 21. Heat is also conducted to this reservoir by the cast iron walls of the casing 10 and radiated to it from the arms 23. The efiect of this is constantly to preheat the liquid fuel in this reservoir and to convert it in the conduits 22 into vapor. Finally, after the oil at the top is burned, the level ofthe liquid in the well will descend to a point below the openings into the grooves, in other words, below the bottoms of the grooves about to the level indicated by the dot and dash line in Fig. 3. The conduits 22 are deep enough so that they always hold a thin layer of oil at the bottom and vapor in the upper part after the burner starts to operate in the normal manner. Thus the liquid fuel will no longer enter the grooves but it will be replaced by combustible vapor which, as soon as it reaches the grooves will continue to rise into the perforated sleeve, allowing the air to mix with the vapor and ignite at a point higher than the grooves. Thereafter the fumes will burn with a blue flame from the vapor itself. The flames are confined to the space above the grooves where combustion takes place. This insures a very hot flame, increasing in intensity as it reaches the top of the perforated sleeves.

After the first operation above described there will be no further conduction of the liquid into the concentric annular grooves and the combustion of the fuel will be uniform and con tinuous. The result is an intensely hot flame at all times until the oil is turned off. After that the oil left in the well will be consumedbefore the flame will go out but always in the form of .vapor.

It will be noted that the tube 17 and well 15 are larger than necessary merely to conduct the oil and that the area of the reservoir is still greater. Therefore there are no restricted passages or pipes which can cool off and cause the formation of carbon deposits. This eliminates a very potent source of trouble in the ordinary oil burner. There is no clogging of the burner and very seldom, if at all, any need of cleaning the burner or the parts below it.

Furthermore the liquid fuel, after the burner is well started, cannot itself ignite as the flame is produced at a level above the tops of the grooves where no liquid fuel can penetrate. It is a high burning flame for these reasons and for the reason that the air to support combustion is admitted only through the perforations in the tubes 14 at a level considerably above the top of the casting 10 and its grooves 11 and 12.

What I claim is:

1. A circular burner base provided with a central well, burner grooves, and a reservoir for liquid fuel at the bottom of said well, said reservoir being of generally circular shape and of a thin fiat construction parallel with the plane of the burner base, of substantially the same area as the burner base and located near it so as to receive, heat from the burner base.

2; The combination with a burner base having a groove disposed in a substantially horizontal plane, and a combustion chamber located there'- above, of a horizontally disposed reservoir for liquid fuel spaced a short distance below the burner in heat receiving relation thereto and of substantially the same area, and a well of substantial diameter connecting the burner base and reservoir for unrestrictedly conducting the liquid fuel upwardly from the reservoir to the burner base, cross conduits connecting said well and groove, the level of the bottom of said conduits being below the level of the bottom of said groove and below the normal level of fuel oil in the burner while in operation, whereby said conduits will form vaporizing chambers.

3. A liquid fuel burner comprising a base having an open topped groove, a vertical tube extending down from the bottom of said groove, a reservoir for liquid fuel disposed below the base and communicating with the bottom of said tube, said reservoir having an area substantially equal to that of the burner base and being located with the top surface parallel to the top surface of the burner base, and a series of passages extending from said tube into the bottom of said groove, and of a depth permitting the heat from the burning fuel to vaporize some of the liquid fuel in the passages so that said passages will conduct vaporized fuel into the groove.

NAPOLEON R. THIBERT. 

